Hydraulic coupling



Dec. 6, 1938. N, L. ALISON HYDRAULIC COUPLING Filed April 29, 1957 5 Sheets-Sheet 1 INVENTOR NOAH L. AL/so/v I ,0 Q w m m m a J v m v m Q m1rw A TTOR/VEYS 1366- 1938. N. ALISON HYDRAULIC COUPLING 5 Sheets-Sheet 2 Filed April 29, 1957 l/Yl/ENTOI? NOAH L. AL/so/v A T TOR/V5 Y8 6, 1938. N. 1.. ALISON.

HYDRAULIC COUPLING Filed April 29, 1957 5 Sheets-Sheet 5 INVENTOR NOAH L. AL/so/v ATTORNEYS N, L. ALISON 5 Sheets-Sheet 5 Filed April 29, 1957 INVENTOR Alon/r L. Auswv 3y Z Z r 1 Z ATTORNEYS Patented Dec. 6', 193a imirsn STATES PATENT OFFICE I 2.13am nrnnilouc COUPLING Application April 29, 1931, Serial No. 139,786

In Great Britain October 2a, 1936 11 Claims.

invention relates to hydraulic couplings and in particular to variable speed hydraulic couplingsu My invention particularly relates to hydraulic 5 couplings. oi the kinetic type comprising an impeller member having radial or partly radial vanes co-axial with and juxtaposed to a runner member also having radial or partly radial vanes, these members together forming a toroidal working circuit for the coupling liquid.

it is the object of my invention to eliminate the undesirable characteristic known as the flat spot;which means that the relation between speed and the amount of oil in the coupling is l5 not a straight line on a graph indicating these relationships. This condition causes serious trouble in connection with the automatic control of hydraulic couplings. It is the object of this invention to eliminate such objectionable conditions so that the relationship between the speed and the amount of oil in the coupling will be suitably maintained.

This condition is brought about by the presence oi the core ring in variable speed hydraulic couplings as heretofore built, the presence of the core ring apparently impeding the flow oi! the oil in the coupling where the coupling was partially tilled, resulting in erratic and undesirable characteristics.

It is an object 01' my invention to provide a novel construction and method of operation depending thereon which permits or a substantially normal oil movement and a balanced oil movement irrespective of the quantity oi oil remain-'- 5 ing in the coupling.

' It is an obiect of niy invention to provide a slotted core ring.

it is a further object to provide a coupling having a plurality of radial ribs with a complete absence of the core ring.

Referring to the drawings: Figure 1 is a vertical section. through a coupling of the prior art showing a continuous hollow core ring fully filled with liquid.

Figure 2 is a section on the line 2-! of Figure 1 looking in the direction the arrows at the impeller with the runner removed ahowing'the continuous core ring. v

Figure 3 is a section on the line 1-4 of Figure 2, which view is developed on that section.

Figure 4 is a view of this constructionfwith the body of oil de-iormed when only a portion of the oil is in the coupling.

Figure 5 is a similar view to Figure 4.

Figure 6 is a view oi'another prior art type 01' coupling with a solid core ringshowing the liquid partially emptied from the coupling and deformed.

Figure '7 is a similar view using a solid core ring. but with a greater quantity of oil in the coupling.

Figure 8 illustrates a vertical section through a coupling of my invention, said section being taken on the line 8-8 of Figure 9. v

Figure 9 is a section on the line 9-9 of Figure 10 8 showing the separated ribs with the core ring severed in spaced radial sections.

Figure 101s a section onthe line ifi-ill of Figure 9 developed.

Figure 11 is a diagrammatic view of the 0011- pling of my invention showing the symmetrical bodyof oil with a portion of the oil evacuated from the coupling.

Figure 12 is a similar view with a greater amount of oil within the coupling.

Figure 13 is a modified form of the coupling of my invention in which there are employed spaced, arcuate reinforcing ribs that are cast integral with the radial plates in each. half of the coup s- Figure 14 is Figure 13.

Figure 15 is a section on the line iE-IB of Figure 14.

Figure 16 is a diagrammatic view of this moditied form of coupling with a portion of the oil evacuated. I

Figure 1"! is a similar view with a lesser amount of oil evacuated.

Figure 18 is a modified form of the coupling illustrated in a view similar to Figure 15 in which the reinforcing and guiding rib has been eliminated.

It is usual to provide prior art couplings with core snide members in the form of two dished rings, mounted respectively on the impeller and the runner vanes, and juxtaposed to form a ring 01' substantially circular section. Thus the wellknown Vulcan" coupling is provided with core guide rings and the vanes are continued within the core space. In the Vulcan-Sinclair" coupling, on the other hand, the core space is usually not vaned, and in the case of the scoop-tube type of coupling the two dished core guide rings 25 a section on the line i4-l4 of are usually fitted with flat core-filling plates which seal the interior of the core from the cir- I cuit, or the core guide rings are of solid instead of hollow construction.

Such hydraulic couplings have certain objections. For example, where a Vulcan or a "Vulcan-Sinclair coupling, having means whereby the liquid content can be varied during operation, is employed to couple a constant-speed driving motor to a variable-speed load, particularly a load, such as a fan, the torque of which varies as the square of the speed, a flat spot occurs in the curve relating liquid content of the coupling to slip, the'slip remaining substantially constant over an appreciable range of filling. This fiat Another known form of hydraulic coupling having a toroidal working circuit is not provided with core guide members; and although this form has no serious fiat spot in its characteristic curve, it suffers from surging, that is to say, fairly rapid and very large variations in its torque transmission capacity over a critical range of filling when the slip is high. Furthermore, this last form of coupling has a higher slip, other things being equal, than a Vulcan and a Vulcan-Sinclair" coupling, and in consequence its efiiciency islower.

An object of my invention is to provide an improved form of hydraulic coupling in which the objections hereinbefore referred to are reduced or overcome.

According to my invention, a hydraulic coupling of the type set forth comprises a plurality of core guide elements distributed in spaced rela- According to my invention, a hydraulic coupling.

' These elements preferably have the same section--semi-circular, hollow D or solid Das the known core guide members, the new construction being in effect a known construction with the core guide ring interrupted at intervals round the coupling axis. The improved interrupted core guide ring is preferably provided on both impeller and runner. However, either vaned element may be provided with an interrupted core guide ring and be associated with a vaned element having a normal core guide ring, or without a core guide ring.

Referring to the drawings in detail and in particular to Figures 1 to 7 showing the prior art, it will be noted that the common defect due to the presence of the core ring when there is less than a full quantity of oil in the coupling is that the rotating body of oil is deflected and de-formed, which brings about, as I have discovered after a careful and extended investigation of this condition, the disturbance of the relation between that it is not possible for the oil to circulate through the core guide ring when the coupling is only partially filled. This was discovered after a great many experiments were made, utilizing a wide variety of structures in an endeavor to 5 solve the problem aforementioned.

My invention is set forth in the remaining views, which show the'arrangement by which the oil is permitted to pass through from one-half of the coupling to another when partially filled. While it is desirable to maintain in certain installations the general continuity of the core ring, both for the guiding of the oil and for reinforcing the ribs, yet it is possible to utilize my invention without such reinforcements on the ribs. In Figures 8 to 12 a coupling is made with the core ring as in the prior art and the slots are milled through the core ring as indicated. In Figures 13 to 1'7 the vanes are cast with semi-circular ribs on either side thereof. In Figure 18 the ribs are not provided with any guide rings or reinforcements.

In the prior art constructions there was employed as illustrated in Figures 1, 2 and 3 the usual drive shaft I having an impeller 2 with a plurality of radial ribs 3 and l, midway of which there was a semi-circular core ring 5 that extended continuously around the face of the ribs and matched with a similar semi-circular core ring 6 carried on the ribs 1 and 8 of the .runner 9. l designates the impeller housing and ii a. casing. l2 designates the runner shaft. It will be understood that the oil makes its exit between the halves of the coupling radially 'through the space 12a.

As will be noted from the drawings, particularly Figures 4 and 5, when the oil was partially removed from the coupling, the rotating body of the oil, instead of being symmetrical, was deformed into a lopsided or kidney shaped and eccentrically-positioned body of oil, which I discovered brought about the disruption in the relation between speed and the amount of oil in the coupling. This was also brought about by the solid core ring shown in Figures 6 and 7.

In the invention herein disclosed, I have slotted the core ring as at l3 so that each of the guide vanes 3, 4, l and 8 will have a section I4 that will be semi-circular, extend partially on either side of the vane, but which will provide free passage between these sections M in the passageway l3 for a. substantially symmetrical rotation of the oil body, and this symmetrical form substantially remains, irrespective of the quantity of the oil within the coupling, thereby giving a uniform relationship between speed and oil volume in the coupling. Likewise in Figures 13 to 17 where the same principle is employed, the semi-circular ribs Ma are caston either side of the vanes. In Figure 18 where these ribs are not necessary in certain types of installations, the vanes are entirely free of any reinforcing or guiding ribs.

In operation, when the filling is only partial,

the driven half of the coupling will establish a certain'speed and with the addition of a small amount of oil this speed will not be materially changed if this oil cannot circulate freely on account of the core'guide ring, as in Figures 1 to 'I. However, when sufficient oil was added to bring the level up to that indicated by the arrows in Figure 5, a big change in speed took place due to the fact that at this filling the oil began to break over the core guide ring and form a circuit around it. From that point on the speed increased more or less in direct ratio with the addition of oil. It was found that at the point between the filling shown in Figure 4 and the filling shown in Figure the flat spot" occurred. The same was true of Figures 6 and 7.

By my invention it is possible for the oil to circulate through the core guide ring when the 15 guide ring as in Figures 8 to 12 and circulate freely with any degree of filling. The same thing is also true of the modified forms in Figures 13 to 17 and Figure 18.

This improved couplinghas a lower minimum slip than an ordinary Vulcan or a Vulcan- Sinclair coupling. It has no substantial flat spot at loads which reveal the flat spot with known couplings having core guide members. Its characteristic curve of quantity to slip at constant impeller speed has a better general shape than the corresponding curve of the known couplings, particularly when driving fans and like loads. Furthermore, the improved coupling is less subject to uncontrollable surging, and it is easier to construct owing to simplification of the cores required in casting the vaned elements. The vanes on which the core guide elements aremounted may be continuous across the ends of these elements, or across them at an intermediate point where an element is longer than a vane interval. ruptions preferably circuit.

It will be understood that I desire to compreextend into the core of the hend within my invention such modifications as may be clearly embraced within the claims and scope of my invention.

Having thus fully described my invention, what I claim'as new and desire to secure by Letters Patent, is:

1. In a variable speed hydraulic coupling having an impeller and runner with oppositely disposed vanes and a core guide ring, the combination therewith of means constituting cut away core guide portions for permitting the oil to circulate through said core guide ring in a direction substantially parallel to the axis of rotation of said coupling when the coupling is only partially filled with oil.

2. In combination, in a variable speed hying vanes and a segmental core ring, sections thereof being mounted in apposition to one another to provide liquid passageways between adjacent segments whereby it is posible for the oil to circulate through said core guide ring when the-coupling is only partially filled.

3. In oombination,in a hydraulic coupling, of an impeller and a runner having radially-disposed vanes, and separated core guide segment means thereon for guiding oil in said coupling in a working circuit, said means being in the form of semi-circular segregated segments so arranged as to make it possible for the oil to circulate therethrough when the coupling is only partially filled with oil to produce a progressive change in the distribution and formation of the -liquid vortex body of oil in the coupling so that posed vanes, and a transversely ported core guide ring so arranged that it is possible for the oil in the coupling to circulate therethrough and from The vanes lying in the inter-- one side of said core guide to the other when the coupling is only partially filled.

5. In combination, in a hydraulic coupling, of an impeller and runner oppositely disposed having radial vanes, and means on each of said vanes comprising semi-circular enlargements circularly disposed on said vanes, with wedgeshaped spaces therebetween whereby it is possible for oil to circulate therebetween when the coupling is only partially filled with oil and to be guided in its rotation between said vanes.

6. In combination, a variable speed hydraulic coupling having an impeller and a runner and shafts therefor, said impeller and runner being provided with a plurality of radially disposed vanes, and segmental spaced radial means on at least a part of said vanes for guiding the oil in the coupling in a rotary path between said guide vanes and so arranged as to permit the rotary movement of the oil transversely across said guiding means when the coupling is only partially filled with oil.

7. In a hydraulic coupling, an impeller and a runner having radially-disposed opposed vanes, and semi-circular slotted means with oil circulating spaces between the adjacent sections mounted on said vanes in apposition one to the other for guiding the oil between the vanes in a substantially symmetrical liquid vortex body in its rotary movement around and between said means so that oil fiow is permitted transversely through the core guide space by means of the spaces between the adjacent semi-circular slotted means.

8. In. a variable speed hydraulic coupling, the combination of an impeller and a runner having vanes and opposite halves of a core ring slotted to guide the fluid in the working circuit whereby the separate sections of the core ring are carried upon said vanes and the oil flow is permitted transversely through the core guide space by means of the spaces between the adjacent,

spaced, core guide ring slotted portions.

9. In a variable speed hydraulic coupling, the combination of an impeller and a runner having radial vanes and a core guide ring at least partially severed transversely of the'ring to permit of oil movement transversely of the ring at intervals.

10. In a variable speed hydraulic coupling, the I combination of an impeller and a runner having coreguide members, at least one of which members is at least partially transversely severed to permit of the transverse movement of oil in the coupling relative thereto.

11. In a hydraulic coupling, the combination of an impeller and runner having vanes and annularly disposed core guide members integral with said vanes; said core guide members being provided with liquid pasageways transversely thereof to permit liquid to pass across the space defined by said core members in a direction substantially parallel to the axis of rotation of said coupling, said passageways thereby effecting a progressive change in the size of the liquid vortex formed around said core guide members when the impeller is rotating and liquid is being introduced or withdrawn from the coupling.

NOAH Les-ran ALISON. 

